- Flat racks handle cargo that does not fit in standard containers. No side walls, no roof. Cargo can protrude beyond the platform bed on all four sides, subject to road and port handling limits. OOG cargo is classified as out of gauge, not oversized, in shipping terminology.
- Two main types: fixed-end and collapsible. Fixed-end flat racks have permanent end walls for structural rigidity. Collapsible flat racks fold flat for efficient empty repositioning. Most heavy machinery exports from China use fixed-end flat racks.
- Payload ratings range from 30 to 45 tons. A 20ft flat rack holds up to 31 tons net payload; a 40ft flat rack holds up to 40-45 tons. The cargo weight plus lashing gear must stay within the flat rack's maximum gross weight (typically 45,000 kg for 40ft).
- Lashing plans are mandatory. Every flat rack shipment requires a lashing plan accepted by the shipping line before loading. The plan must reference the IMO CSS Code and show lashing points, equipment types (chains, tensioners, wire ropes), calculated forces, and MSL (Maximum Securing Load) values.
In This Guide
- What Is a Flat Rack Container
- Flat Rack Types: Fixed-End vs Collapsible
- Cargo Suitable for Flat Racks
- Flat Rack vs Open Top vs Platform Container
- Lashing and Securing Requirements
- Flat Rack Costs from Chinese Ports
- Flat Rack Availability at Chinese Ports
- Frequently Asked Questions
- How to Ship Flat Rack with Great Hensen
1. What is a flat rack container
A flat rack container is an ISO-standard intermodal container with a flat bed platform, no side walls, and no fixed roof. According to the International Maritime Organization (IMO), flat racks are classified under the CSC (International Convention for Safe Containers) and must carry a valid CSC Safety Approval Plate, the same as any standard ISO container. It has end walls (vertical panels at both short ends) that can be either permanently fixed or collapsible. The open sides and open top allow cargo to be loaded from above or from the side, using cranes, forklifts, or roll-on methods. Flat racks are the standard equipment for OOG (Out of Gauge) cargo, freight that exceeds the internal dimensions of a standard dry container.
Unlike a standard container that encloses cargo in a steel box, a flat rack exposes cargo to the elements. Weather protection must be arranged separately when needed. In practice, many types of industrial equipment do not require weather protection and ship uncovered.
Standard Flat Rack Dimensions and Ratings
| Specification | 20ft Flat Rack | 40ft Flat Rack |
|---|---|---|
| Internal length | 5,940 mm (19'6") | 12,080 mm (39'7") |
| Internal width | 2,350 mm (7'9") | 2,350 mm (7'9") |
| Internal height (with end walls) | 2,253 mm (7'5") | 1,950 mm (6'5") |
| Tare weight | 2,500-2,900 kg | 5,300-6,100 kg |
| Max gross weight | 34,000 kg (some: 40,000 kg) | 45,000 kg |
| Max payload (net) | 31,100-31,500 kg | 38,900-39,700 kg |
| Cargo can overhang? | Yes, within road/port limits | Yes, within road/port limits |
| Stackable when empty? | Collapsible only, up to 4 high | Collapsible only, up to 4 high |
2. Flat rack types: fixed-end vs collapsible
Flat racks come in two structural configurations. According to the China Port and Harbor Association, flat rack container demand at Chinese ports has grown in line with the expansion of heavy equipment and renewable energy component exports. The choice affects loading method, cargo protection, structural rigidity, and repositioning cost for the carrier.
Fixed-End Flat Rack
End walls are permanently welded to the platform bed. These end walls provide structural rigidity and protect cargo from longitudinal forces (braking and acceleration during sea and road transport). The fixed end walls allow lashing gear to be attached to multiple securing points along the end wall frame, distributing force more evenly than collapsible models.
- Advantage: Higher structural strength, more lashing points, better protection at ends.
- Disadvantage: Cannot be stacked compactly when empty, repositioning costs are high for unbalanced trade lanes.
- Best for: Heavy machinery above 20 tons, cargo that needs end-wall lashing points, one-way shipments where return repositioning is factored into the freight rate.
Collapsible Flat Rack
End walls are hinged and can be folded flat against the platform bed. When collapsed, four units can be stacked vertically, reducing the repositioning footprint by 75%. This makes collapsible flat racks the preferred equipment on trade lanes with significant cargo imbalance, such as China to Africa or China to South America, where carriers need to return empty units efficiently.
- Advantage: Efficient empty repositioning, wider availability on imbalanced trade lanes, lower repositioning surcharge.
- Disadvantage: Slightly lower structural rigidity than fixed-end, fewer lashing points on end walls.
- Best for: Cargo under 25 tons, routes with cargo imbalance (e.g., China to Middle East or Africa), shipments where carrier equipment availability is a concern.
For most heavy machinery exports from China, we recommend fixed-end flat racks. Chinese manufacturers exporting excavators, bulldozers, transformers, and generators almost always ship on fixed-end 40ft flat racks because the cargo weight exceeds 25 tons and the end-wall lashing points are essential for a compliant securing arrangement. For details on heavy equipment handling, see our heavy equipment flat rack case study.
3. Cargo suitable for flat racks
Flat racks solve three cargo problems: width that exceeds 2.35 m (standard container internal width), height that exceeds 2.39 m (standard HC internal height), or concentrated weight that exceeds the floor loading of a standard container. If your cargo hits any one of these limits, it needs a flat rack or open top container.
Cargo Categories That Routinely Ship on Flat Racks from China
| Category | Examples | Typical Weight | Common Origin Ports |
|---|---|---|---|
| Construction machinery | Excavators, bulldozers, wheel loaders, road rollers, graders, crawler cranes | 15-45 tons | Qingdao, Shanghai, Tianjin |
| Industrial equipment | Generators, transformers, gas turbines, compressors, boilers, reactor vessels | 10-40 tons | Shanghai, Qingdao, Tianjin |
| Steel and pipe products | Steel coils, line pipe, drill pipe, structural steel beams, prefabricated steel components | 10-30 tons | Qingdao, Tianjin, Shanghai |
| Project cargo / EPC freight | Factory equipment for overseas relocation, power plant components, cement plant machinery | 5-45 tons per unit | All major Chinese ports |
| Wind energy components | Wind turbine nacelles, hubs, tower sections (not blades, those need special fixtures) | 20-40 tons | Tianjin, Shanghai, Qingdao |
| Offshore and marine parts | Deck equipment, winches, anchors, propeller assemblies, marine engines | 5-30 tons | Qingdao, Shanghai, Dalian |
| Vehicles and trailers | Concrete pump trucks, mobile cranes, special-purpose vehicles, agricultural combines | 10-35 tons | Shanghai, Qingdao, Tianjin |
Cargo That Should NOT Go on a Flat Rack
- Cargo that fits in a standard container. If your cargo is within 2.35 m width and 2.39 m height, use a standard 40ft HC. Flat rack rates are 1.5x-3x higher, so using one unnecessarily adds cost without benefit.
- Tall cargo with standard width. Cargo that is too tall but fits within standard container width should use an open top container, not a flat rack. Open tops provide side wall protection and weather cover. See section 4 below for the comparison.
- Cargo requiring full enclosure. Sensitive equipment that cannot be exposed to salt spray, rain, or sun during the 30-45 day ocean transit should ship in a standard container or be fully crated before loading on the flat rack.
- Cargo over 45 tons per unit. This exceeds the gross weight limit of standard flat racks and requires breakbulk (non-containerized) shipping with specialized heavy-lift vessel handling. Our heavy-lift and project cargo service covers breakbulk options for loads above 45 tons.
4. Flat rack vs open top vs platform container
Three container types handle non-standard cargo. According to the China Ministry of Transport (MOT), correct container type selection for oversized cargo is critical for transport safety. Choosing the wrong one causes unnecessary cost or inadequate cargo protection. Here is how to choose.
| Feature | Flat Rack | Open Top | Platform |
|---|---|---|---|
| Side walls | None | Yes, solid steel | None |
| End walls | Yes (fixed or collapsible) | Yes, solid | None (end beams only) |
| Roof | None | Open top, tarpaulin cover | None |
| Side loading | Yes, from all sides | No, only from top | Yes, from all sides |
| Top loading | Yes, by crane | Yes, by crane (remove tarpaulin) | Yes, by crane |
| Cargo exposure | Full exposure to elements | Side protected, top exposed (tarpaulin cover) | Full exposure |
| Best for width | Up to road/port limit | Within container width (2.35m) | Up to road/port limit |
| Best for height | Unlimited (within road/port) | Up to 3.5m with tarpaulin | Unlimited |
| Max payload (40ft) | ~39 tons | ~26.5 tons | ~39 tons |
| Weather protection | None (cargo covers optional) | Side walls + tarpaulin | None |
| Typical use case | Heavy machinery, pipes, over-width/over-height OOG cargo | Tall machinery within standard width, top-loaded cargo | Ultra-heavy, non-stackable breakbulk integrated into container vessel |
Decision Rule
- Cargo is wider than 2.35 m: Flat rack. No other container type handles over-width cargo.
- Cargo is taller than 2.7 m but within standard width: Open top, if weight is within the open top's lower payload limit (26.5 tons for 40ft). If weight exceeds 26.5 tons, use flat rack.
- Cargo is both over-width and over-height: Flat rack. This is the most common OOG scenario from Chinese manufacturers.
- Cargo is over 45 tons and cannot be reduced: Platform container or breakbulk. Platform containers have no end walls at all, just a flat steel bed with corner castings, and can handle higher concentrated loads. For loads above platform limits, breakbulk shipping is the only option.
5. Lashing and securing requirements
Lashing is the most technically demanding part of flat rack shipping. A flat rack loaded with 40 tons of machinery on a vessel rolling in 5-meter swells exerts enormous dynamic forces. Inadequate lashing causes cargo shift, equipment damage, and in severe cases container loss at sea. Every flat rack shipment requires a lashing plan accepted by the carrier before the container moves to the terminal.
Regulatory Basis: IMO CSS Code
Lashing of cargo on flat racks is governed by the IMO Code of Safe Practice for Cargo Stowage and Securing (CSS Code), specifically Annex 13 for non-standardized cargo. The code requires calculation of securing forces against the following accelerations:
- Transverse (side-to-side): 0.7g on deck stowage (higher than below deck because of vessel roll)
- Longitudinal (front-to-back): 0.3g on deck stowage
- Vertical (up-down): 0.3g upward, 0.5g downward on deck stowage
Lashing Equipment
| Equipment | MSL (Maximum Securing Load) | Best For | Notes |
|---|---|---|---|
| Steel chain with tensioner | 10,000-16,000 daN (10-16 tons) | Heavy machinery above 10 tons | Standard for flat rack heavy cargo. Use Grade 80 or higher. |
| Wire rope lashing | 5,000-10,000 daN | Steel products, pipes, structural beams | Flexible, easier to tension around irregular shapes. Inspect for kinks. |
| Polyester web lashing | 2,000-5,000 daN | Lighter equipment, vehicles | Not recommended for cargo above 15 tons. UV degradation over time. |
| D-rings and lashing eyes | 5,000-10,000 daN each | Attachment points on flat rack bed | Flat rack beds have 8-16 integral lashing points. Verify count before booking. |
| Wood dunnage and friction mats | Increases friction to mu=0.3-0.6 | Base layer under all cargo | Essential for friction-based securing. Rubber mats for steel-on-steel contact. |
| Shrink wrap / tarpaulin | Weather protection only, no securing value | Corrosion-sensitive equipment | Add desiccant packs under wrap for ocean transit moisture control. |
Minimum Securing Points by Cargo Weight
- Cargo under 10 tons: Minimum 4-point tie-down with web lashings or light chains.
- Cargo 10-25 tons: Minimum 6-point tie-down with steel chains, 4 transverse + 2 longitudinal.
- Cargo 25-40 tons: Minimum 8-point tie-down with Grade 80 steel chains and tensioners. Each chain must have MSL of at least 10,000 daN. Diagonal lashing from cargo lifting points to flat rack D-rings recommended for redundancy.
- Cargo over 40 tons: Above requirements plus diagonal bracing and blocking. A professional lashing engineer must sign off on the plan.
- Undertightened chains. A tensioner must be used. Hand-tight is not enough. Chains loosen during transit.
- No friction mat under steel cargo. Steel on steel has a friction coefficient of mu=0.1. A rubber or wood mat raises this to mu=0.3-0.5, reducing required lashing force by 60-70%.
- Lashing at wrong angle. Vertical lashing alone does not prevent sliding. Chains must have a horizontal component (30-60 degrees from horizontal).
- No edge protection. Sharp cargo edges cut through web lashings. Use edge protectors (steel corner guards) at every contact point.
For project cargo shipments, the lashing plan is prepared by our in-house heavy-lift team and submitted to the carrier for approval 5-7 working days before loading. The plan includes a force calculation table, lashing equipment list with MSL values, a diagram showing all lashing points and angles, and photographs of the cargo with lifting/lashing points marked. See our overseas engineering project logistics case study for a real example.
6. Flat rack costs from Chinese ports
Flat rack freight is more expensive than standard FCL on the same route. The premium covers the slot loss (a flat rack occupies more than one container slot on the vessel), the specialized equipment scarcity, and the additional terminal handling complexity. Here is what you actually pay.
Freight Rate Comparison: Flat Rack vs Standard FCL (from Chinese ports, USD, July 2026)
| Route | 40ft Standard FCL | 40ft Flat Rack (Est.) | Flat Rack Premium |
|---|---|---|---|
| Qingdao to Rotterdam | $2,800-4,500 | $5,500-9,000 | 1.8x-2.5x |
| Shanghai to Hamburg | $2,700-4,300 | $5,200-8,500 | 1.8x-2.5x |
| Qingdao to Santos | $3,500-5,500 | $7,000-13,000 | 2.0x-2.8x |
| Shanghai to Jebel Ali | $2,200-3,800 | $4,500-8,000 | 1.8x-2.5x |
| Qingdao to Mombasa | $3,000-5,000 | $6,500-12,000 | 2.0x-2.8x |
| Shanghai to Los Angeles | $2,500-5,000 | $5,000-10,000 | 1.8x-2.3x |
Rates are estimated market ranges for July 2026. Actual rates depend on carrier, season, cargo weight, and OOG dimensions. These are freight-only (FOB port to port), excluding origin and destination charges. Get a custom quotation for your specific cargo.
Additional Cost Components
- OOG surcharge: Typically $500-2,000 per flat rack, calculated by the carrier based on the total occupied footprint (bed dimension plus overhang on all sides). Larger overhang = higher surcharge.
- Heavy-lift surcharge: Applied when cargo net weight exceeds 25 tons. Typically $10-20 per ton for the portion above 25 tons. A 38-ton cargo pays heavy-lift surcharge on 13 tons.
- Lashing plan preparation: $200-500 per plan, prepared by a qualified lashing engineer with force calculations and carrier acceptance.
- On-site lashing labor: $300-800 per flat rack at Chinese ports, including lashing materials (chains, tensioners, dunnage). Materials cost varies with cargo weight and lashing points.
- Terminal handling: $100-200 surcharge above standard THC (Terminal Handling Charge) for flat rack units, reflecting crane and yard handling complexity.
- Customs inspection of oversized cargo: Chinese customs may require physical inspection of OOG units. If selected for inspection, expect $150-400 in associated fees and a 1-3 day delay.
Ocean freight: ~$6,500 (mid-market rate) + OOG surcharge: ~$800 + Heavy-lift surcharge (13 tons overweight): ~$200 + Lashing plan: $300 + On-site lashing: $500 + THC surcharge: $150 = Approximately $8,450 total. Budget $8,000-10,000 for a single 40ft flat rack from Qingdao to Europe in July 2026.
7. Flat rack availability at Chinese ports
All major Chinese container ports handle flat racks. The deciding factors for which port to use are your factory location (inland transport cost and road permit feasibility), carrier sailing frequency to your destination, and the terminal's crane capacity for heavy units. Here is how the major ports compare for flat rack operations.
| Port | Flat Rack Availability | Crane Capacity | Heavy-Lift Handling | Best For |
|---|---|---|---|---|
| Qingdao | Good. All major carriers (MSK, HPL, MSC, COSCO, HMM, OOCL, EMC, YML, CMA CGM) stock flat racks. Home port of Great Hensen. | Container gantry: 65 tons. Heavy-lift quay crane: 100 tons. | Specialized heavy-lift terminal at Qianwan Phase 4. Dedicated OOG cargo yard. | Shandong, Hebei, Henan factories. North China heavy machinery exporters. SANY, Shantui, Sinotruk shipments. |
| Shanghai | Excellent. Largest flat rack inventory in China. All carriers stock both 20ft and 40ft. | Yangshan: 80 tons container gantry. Waigaoqiao: 65 tons. | Yangshan deep-water terminal preferred for units over 35 tons. Waigaoqiao accepted up to 40 tons. | Zhejiang, Jiangsu, Anhui factories. Highest sailing frequency. Best carrier selection. |
| Tianjin | Good. Strong flat rack availability due to high volume of steel and heavy equipment exports. | Container gantry: 65 tons. Multiple heavy-lift cranes: 100-200 tons. | Long-established heavy-lift expertise. Tianjin is China's largest port for steel and industrial equipment exports. | Beijing area, Hebei steel products, northern industrial equipment. Wind turbine components. |
| Ningbo | Moderate. Flat rack stock adequate but limited compared to Shanghai. Book 5-7 days ahead. | Chuanshan terminal: 65 tons. | Handles standard OOG. For ultra-heavy units above 40 tons, Shanghai Yangshan is preferred. | Zhejiang manufacturers. Alternative to Shanghai when that port is congested. |
| Shenzhen (Yantian) | Moderate. Flat racks available but inventory limited on less common routes. Book 7+ days ahead. | Yantian terminal 9: 65 tons. | Overweight containers require 3-day advance notification and terminal bearing test (min 50t/m2). | Guangdong manufacturers. Americas routes (Pacific crossing). |
How to Choose Your Flat Rack Port
- Calculate inland transport cost first. A flat rack with over-width cargo requires a special road transport permit in China. The permit cost and availability varies by province. Shandong, Zhejiang, and Jiangsu have efficient permit systems (1-3 days). Other inland provinces may take longer. Choose the nearest major port whenever possible.
- Check carrier sailing frequency. Not every carrier runs flat rack-accepting vessels on every route from every port. MSK, COSCO, and MSC have the widest flat rack route networks from Chinese ports. CMA CGM and HPL cover most major routes. Always confirm flat rack availability on your specific route before committing to a port.
- Consider crane capacity. If your loaded flat rack gross weight exceeds 50 tons, verify the terminal crane capacity at your chosen port. Yangshan (Shanghai) and Qingdao Qianwan Phase 4 have the highest capacity container gantries (80 tons and 65 tons respectively).
For most heavy machinery exporters in Shandong, Hebei, and Henan provinces, Qingdao is the optimal port. It offers shorter inland transport distances, efficient customs clearance (24-48h from declaration to approval for routine cargo), and Great Hensen's on-site operations team managing every flat rack loading directly at the terminal. Contact us for port-specific routing advice based on your factory location and destination.
8. Frequently asked questions
How far in advance should I book a flat rack from China?
Book 14-21 days before the planned loading date. Flat racks are specialized equipment, not available in unlimited quantities at every port. During peak season (August-October), book 21-28 days ahead. Chinese National Day holiday (first week of October) creates a 2-week booking surge. For urgent shipments, we can source flat racks from alternative carriers within 5-7 days, but rates are higher for last-minute bookings.
Can I load cargo that extends beyond the flat rack bed?
Yes, this is the primary purpose of a flat rack. You must declare the exact OOG dimensions at booking: total length, total width (including left and right overhang from center), and total height from the flat rack bed. Cargo overhang is permitted on all four sides, but the total footprint determines the OOG surcharge. Road transport regulations in the origin and destination countries set the practical limits, not the flat rack itself. In China, road permits are required for loads exceeding 2.55 m width or 4.0 m height.
What is the difference between FOB and CIF for flat rack shipments?
Under FOB (Free On Board, Incoterms 2020), the Chinese supplier or freight forwarder is responsible for inland transport to port, export customs clearance, and loading onto the vessel. The buyer arranges ocean freight and insurance. Under CIF (Cost, Insurance and Freight), the seller arranges and pays for transport and insurance to the destination port. For flat rack shipments from China, we recommend FOB terms with the buyer nominating the freight forwarder for greater control over flat rack sourcing and carrier selection. Most Chinese suppliers default to FOB pricing. Our freight forwarding service handles the complete FOB scope from factory to vessel loading.
Does weather affect flat rack cargo during ocean transit?
Yes. Flat rack cargo is exposed to salt spray, rain, sun, and temperature swings. For machinery and equipment with sensitive components (electrical panels, hydraulic systems, exposed bearings), we recommend weather protection: marine-grade shrink wrap over the entire unit with desiccant packs inside, or custom crating for the most sensitive parts. For bare steel cargo (pipes, beams, fabricated structures), no weather protection is typically needed, standard practice in international shipping of steel products. Ventilation during transit helps prevent condensation under tarpaulins.
Can flat racks carry dangerous goods cargo?
Yes, flat racks can carry DG cargo. Common examples include DG generators (fuel tanks, Class 3 flammable liquids), gas cylinders (Class 2), and battery-equipped machinery (Class 9). The standard IMDG Code DG declaration and packaging requirements apply. The Class 9 placard must be visible on all four sides of the flat rack end walls. For DG cargo with standard dimensions, our DG freight service handles the complete compliance process. Note that some carriers restrict DG cargo on flat racks; we verify carrier acceptance at the booking stage.
9. How to ship flat rack cargo with Great Hensen
- Send us your cargo specs. Dimensions (length x width x height), weight, lifting points, photographs of the cargo from all sides, factory address, and destination port. If the cargo has overhang beyond a standard flat rack bed, provide the exact left and right overhang measurements.
- We return a routing plan and quotation within 24 hours. Recommended port, carrier options, flat rack type (fixed-end or collapsible), total transit time estimate, lashing plan outline, and a fixed quotation valid for 14 days. The quotation includes all FOB charges: inland transport, port handling, documentation, lashing, and ocean freight.
- Lashing plan preparation. Our in-house heavy-lift team prepares the lashing plan (force calculations, equipment list, securing diagram) and submits it to the carrier for approval 5-7 working days before loading. We source the flat rack from our carrier partners and coordinate the empty unit delivery to your loading location or to the port.
- Transport execution. Inland collection from factory (with over-width road permits when needed), port entry and customs clearance, cargo lashing under our supervision, loading onto vessel, ocean freight with real-time tracking, destination port handling, and final delivery. Single point of contact from factory floor to destination.
Get a Flat Rack Shipping Quote
Or call +86 13375320398 | info@GreatHensen.com
Sources and references
- IMO CSS Code (Code of Safe Practice for Cargo Stowage and Securing): Annex 13, Methods to Assess the Efficiency of Securing Arrangements for Non-Standardized Cargo. International Maritime Organization. IMO CSS Code
- ISO 668:2020 Series 1 freight containers: Classification, dimensions and ratings. International Organization for Standardization. Flat rack container specifications and maximum gross mass values.
- IMDG Code Amendment 42-24: mandatory from January 1, 2026. Applicable to flat rack shipments carrying dangerous goods. IMO. IMO IMDG Code
- Incoterms 2020: International Chamber of Commerce (ICC). FOB and CIF definitions for flat rack shipments from Chinese suppliers.
- China Single Window (国际贸易单一窗口): electronic export declaration system used by all Chinese customs ports. China Single Window
- Chinese road transport regulations for over-width cargo: Highway Law of the People's Republic of China and Regulations on the Administration of Over-Limit Transport Vehicles (超限运输车辆行驶公路管理规定). Special road permits required for loads exceeding 2.55 m width or 4.0 m height.
- Carrier flat rack specifications: Based on MSK, COSCO, HPL, MSC, and CMA CGM published equipment guides and flat rack availability data as of July 2026.
- Great Hensen shipping records: 500+ flat rack shipments from Chinese ports since 2018. Representative cost data from Q1-Q2 2026 bookings.
All operational data based on Great Hensen's actual flat rack shipments. Cost ranges are market estimates for July 2026 and should be confirmed at the time of booking. Last verified: July 11, 2026.
Need flat rack shipping from China?
We handle flat rack sourcing, lashing plan engineering, over-width permits, China customs clearance, and ocean freight. Single point of contact from your Chinese factory to destination port.